Laparoscopic surgical instrument having lockable handles with a latch feature

ABSTRACT

A laparoscopic instrument including a first handle and a second handle. The first handle includes a latching mechanism. The second handle is pivotally coupled to the first handle and includes a locking part. The first handle and the second handle are in a locked position when the latching mechanism is engaged with the locking part, and the first handle and the second handle are in an open position when the latching mechanism is disengaged from the locking part. The latching mechanism include a limiting lever that is positioned along the rotational path of the latching lever in order to limit the rotational movement of the latching lever. The latching mechanism allows a surgeon to lock or unlock the handles with the hand that is grasping the handles without using the other hand.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application Ser. No. 60/690,968 filed Jun. 16, 2005, titled “Laparoscopic Tool Coupler,” and U.S. Provisional Patent Application Ser. No. 60/711,347 filed Aug. 25, 2005, titled “Laparoscope's Tool With In Situ Tool Exchange,” each of which is incorporated herein in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to laparoscopic instruments and, more particularly, to a laparoscopic instrument having lockable handles with a latch feature.

BACKGROUND OF THE INVENTION

Laparoscopic instruments are used during laparoscopy procedures, which are generally used to examine a patient and/or to perform minor surgery on the patient. For example, a laparoscopic instrument can be used to examine the patient's abdominal cavity for signs of disease or abnormality. In addition, fully invasive surgery may be avoided by using the laparoscopic instrument to perform relatively minor surgery. Similarly, in minimally invasive arthroscopic procedures, such as on a knee joint, an arthroscopic instrument is used to access joints or bones.

The laparoscopic (or arthroscopic) instrument generally includes a grasping end and an operating end that are connected by a flexible hollow cylindrical shaft. The laparoscopic instrument is introduced into the patient through a cannula/trocar unit. After the laparoscopic instrument is inserted into the patient through a cannula that is anchored to the body via a small incision, the surgeon may insert one of a plurality of laparoscopic tools into the laparoscopic instrument to perform a particular surgical procedure. For example, if a grasping procedure is required the surgeon will insert a grasping tool in the laparoscopic instrument. Similarly, if a cutting procedure is required the surgeon will insert a cutting tool in the laparoscopic instrument.

One problem associated with current laparoscopic instruments is that they may cause the surgeon to lose his or her “feel” when changing laparoscopic tools. During surgery, the surgeon develops a particular “feel” associated with the location and positioning of the laparoscopic instrument relative to the patient's internal cavities. Because the surgeon may be required to perform several procedures during a single surgery, each procedure requiring a different laparoscopic tool, the surgeon may lose the “feel” when changing the laparoscopic tools.

In one exemplary scenario, the surgeon uses an examination tool to find the best location for performing a cutting procedure. After finding the best location, the surgeon retrieves the laparoscopic instrument from within the patient, replaces the examination tool with a cutting tool, and reinserts the laparoscopic instrument inside the patient. It can be time consuming and frustrating for the surgeon to locate, for a second time, the best location for performing the cutting procedure.

Another problem associated with current laparoscopic instruments is that they have a fixed grasping end and, therefore, limit the ability and/or comfort of the surgeon in attaining desired positions within the patient's body. Depending on the surgical procedure, the surgeon must often change the position of the laparoscopic instrument or contort his or her body position to reach various parts of a patient's internal cavity. For example, the surgeon will often attempt to achieve the best cutting position before performing a delicate cutting procedure by rotating and/or moving the grasping end of the laparoscopic tool at various uncomfortable and awkward positions. Because the grasping end of the laparoscopic instrument is fixed, the surgeon must perform the cutting procedure by grasping the laparoscopic tool at an uncomfortable or awkward position that decreases the likelihood of a successful surgical procedure, or must contort his or her body to access a hard-to-reach area of the patient's internal cavity.

Yet another problem associated with current laparoscopic instruments is that the surgeon must clasp the operating end together in order to hold a grasping tool in a closed position. Prolonged clasping results in hand fatigue and also undesirably ties up one of the surgeon's hands to perform other tasks. If the surgeon removes or relaxes his hand from the grasping end, then the grasping tool may lose its grip on the internal body structure it was grasping.

Thus, there is a need to provide a laparoscopic tool that allows the surgeon to retain the “feel” developed during a surgical procedure by changing laparoscopic tools without having to remove the laparoscopic instrument from within the patient's body. There is also a need for an adjustable grasping end for a laparoscopic or arthroscopic instrument for attaining desired and/or comfortable operating positions. There is yet another need for a laparoscopic or arthroscopic instrument that can lock a grasping tool in a fixed position without requiring manual clasping by the surgeon. The present invention fulfills these and other needs.

SUMMARY OF THE INVENTION

A laparoscopic instrument including a first handle and a second handle. The first handle includes a latching mechanism. The second handle is pivotally coupled to the first handle and includes a locking part. The first handle and the second handle are in a locked position when the latching mechanism is engaged with the locking part, and the first handle and the second handle are in an open position when the latching mechanism is disengaged from the locking part. The latching mechanism may include at least one latching tooth and the locking part includes at least one locking tooth, the latching tooth being engaged to the locking tooth in the locked position. The latching mechanism may further include a latching lever pivotably coupled to the first handle. The latching lever is aligned with the first handle in the locked position. A free end of the latching lever can be pivotable in a direction away from the first handle to achieve the open position. The latching mechanism may include a lever limiter positioned along the rotational path of the latching lever for limiting the rotation of the latching lever. The lever limiter can be coupled proximate a free end of the latching lever. The latching mechanism may include a latching teeth-engaging part attached to a free end of a latching lever and the locking part includes a locking teeth-engaging part. The latching lever is pivotally coupled to the first handle at a fixed end, and the latching lever is aligned with the first handle in the locked position. The latching teeth-engaging part is aligned and engaged to the locking teeth-engaging part when the first handle is in the locked position.

In another aspect of the present invention, a method is directed to locking and unlocking a first handle of a laparoscopic instrument relative to a second handle. The method includes urging the first handle towards the second handle to engage a latching mechanism of the first handle to a locking part of the second handle. The method may include biasing the latching mechanism against the locking part to secure a plurality of teeth to each other. At least one of the plurality of teeth may be located on the latching mechanism and a corresponding one of the plurality of teeth may be located on the locking part. The method may further include pivoting the latching mechanism away from the first handle to unlock the first handle from the second handle. The method may still further include mounting the latching mechanism on a latching lever pivotally coupled to the first handle and rotating a free end of the latching lever to disengage the latching mechanism from the locking part. The method may further include limiting the pivoting motion of the latching lever using a lever limiter. The lever limited may be coupled to the first handle proximate the free end of the latching lever. The method may also include rotating the free end of the latching lever in a direction that is substantially perpendicular to the pivoting direction of the first handle towards the second handle. Still further, the method may include coupling the latching mechanism to a grasping end of the first handle.

In still another aspect of the present invention, a laparoscopic instrument includes a pair of handles that are pivotable between a locked position and an open position. The laparoscopic instrument further includes a latching lever, a lever limiter, a tooth-engaging part, and a locking part. The latching lever is pivotally coupled to a trigger handle of the pair of handles at a pivoting point. The lever limiter is coupled to the trigger handle near a free end of the latching lever and is directed to restricting the pivoting motion of the latching lever. The tooth-engaging part is coupled to the trigger handle. The locking part is coupled to a fixing handle of the pair of handles such that the locking part is engaged to the tooth-engaging part when the pair of handles is in the locked position, and such that the locking part is disengaged from the tooth-engaging part when the pair of handles is in the open position. The locking part may be biased towards the tooth-engaging part via a frictional force exerted by at least one pair of interlocking teeth.

The above summary of the present invention is not intended to represent each embodiment, or every aspect, of the present invention. Additional features and benefits of the present invention are apparent from the detailed description, figures, and claims set forth below.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A is an exploded perspective view showing a first portion of a laparoscopic instrument according to one embodiment of the present invention.

FIG. 1AI is a perspective bottom view of the tool drum shown in FIG. 1A according to an embodiment of the present invention.

FIG. 1B is an exploded perspective view showing a second portion to the laparoscopic instrument shown in FIG. 1A.

FIG. 2 is an assembly perspective view of the laparoscopic instrument of FIGS. 1A and 1B.

FIG. 3 is a front view of the laparoscopic instrument of FIGS. 1A and 1B.

FIG. 4 is a top view of the laparoscopic instrument of FIGS. 1A and 1B.

FIG. 5 is a back view of the laparoscopic instrument of FIGS. 1A and 1B.

FIG. 6 is a bottom view of the laparoscopic instrument of FIGS. 1A and 1B.

FIG. 7 is a left-side view of the laparoscopic instrument of FIGS. 1A and 1B, showing a tool end of the laparoscopic instrument.

FIG. 8 is a right-side view of the laparoscopic instrument of FIGS. 1A and 1B, showing a handle-end of the laparoscopic instrument.

FIG. 9 is an exploded perspective view showing a drum subassembly of the laparoscopic instrument of FIGS. 1A and 1B.

FIG. 10 is an assembly perspective view showing interior details of the drum subassembly of FIG. 9.

FIG. 11 is a planar cross-sectional view of the drum subassembly of FIG. 9.

FIGS. 12A-12C are perspective views of an assembly comprising a winged shaft and a handle drum according to three alternative embodiments of the present invention, respectively.

FIG. 13 is a cross-sectional view representing the interaction between a winged shaft and a drum subassembly according to an embodiment of the present invention.

FIG. 14 is a perspective cross-sectional view of the drum subassembly of FIG. 9 showing a push-button in a fully depressed position and a pair of handles in a first position.

FIG. 15 is a perspective cross-sectional view showing the push-button of FIG. 14 in the fully depressed position and the pair of handles in a second position.

FIG. 16 is a perspective cross-sectional view showing the push-button of FIG. 14 in an un-depressed position and the pair of handles in the second position.

FIG. 17 is a partial exploded perspective view showing a shotgun subassembly of the laparoscopic instrument of FIGS. 1A and 1B in an open breech position.

FIG. 18 is a perspective view of the shotgun subassembly of FIG. 17 in an open breech position exposing an insertion end of a laparoscopic tool.

FIG. 19 is a perspective view of the shotgun subassembly of FIG. 17 showing an assembled shotgun subassembly in an open breech position.

FIG. 20A is a representative diagrammatic front view showing an alternative embodiment of a shotgun subassembly rotating about an X-axis of a laparoscopic instrument.

FIG. 20B is a representative side view of FIG. 20A.

FIG. 21A is a representative top view showing another alternative embodiment of a shotgun subassembly rotating about a Y-axis of a laparoscopic instrument.

FIG. 21B is a representative front view of FIG. 22A.

FIG. 22A is a perspective view of a pair of handles of the laparoscopic instrument of FIGS. 1A and 1B in an open aligned position.

FIG. 22B is a perspective view of the pair of handles of FIG. 22A in a locked position.

FIG. 23A is a perspective view of the pair of handles of FIG. 22A in a closed offset position.

FIG. 23B is a perspective view of the pair of handles of FIG. 22A in an open offset position.

While the invention is susceptible to various modifications and alternative forms, specific embodiments are shown by way of example in the drawings and are described in detail herein. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Referring to FIGS. 1A and 1B, a general description of the parts associated with a laparoscopic instrument 100 is provided according to an embodiment of the present invention. A more detailed description of the parts and their associated movements is provided in subsequent drawings. The laparoscopic instrument 100 includes a push button 102 that has a generally cylindrical disk shape. The push button 102 is connected to a winged shaft 104 via a push-button screw 106, which is inserted through a central hole of the push button 102. The push button 102 is adjacent to a spring 108, which includes one end that is in contact with the push button 102 and another end that is in contact with a tool cover 110.

The tool cover 110 is a generally cylindrical plate that includes a central hole and a plurality of tapped periphery holes. The winged shaft 104 protrudes through the central hole of the tool cover 110 toward the push button 102. Two connecting screws 112 connect the tool cover 110 to a housing 114.

The housing 114 includes a drum receiving portion 116 for accommodating at least in part a tool drum 118, a trigger drum 120, and a fixing drum 122, each of which is located adjacent to one another as shown. The housing 114 further includes a ball-receiving slot 115 for allowing pivoting movement of the housing 114, as described in more detail below in reference to FIGS. 17-19.

Referring to FIG. 1AI, the tool drum 118 is illustrated as being generally cylindrical, having a central through-hole, which is cylindrically shaped, and including a plurality of slots through which the winged shaft 104 protrudes. Although the plurality of slots is shown having three slots, alternatively, any number of slots may be used. The slot height extends only through part of the tool drum 118 (i.e., the slots are not through-slots). For example, the slot height is half the height of the tool drum 118. In alternative embodiments, the slot height extends through the entire tool drum 118. In yet other alternative embodiments, the central hole can have any other three-dimensional shape, e.g., a partial toroid, for receiving the winged shaft 104 therethrough. As explained in more detail below, the slots of the tool drum 118 engage the winged shaft 104 for securing the tool drum 118 to the fixing drum 122 in any one of a plurality of positions.

A drum washer 124 and a plug 126 is located between the tool drum 118 and the housing 114. The tool drum 118 includes a ball-receiving hole 127 along its periphery as shown.

The trigger drum 120 is generally cylindrical and is attached to a trigger handle 128 that includes a latching mechanism 130. The trigger drum 120 is attached to the trigger handle 128 directly or through a mechanical linkage. The trigger drum 120 includes a central slotted hole having substantially the same shape and dimensions as the slotted hole of the tool drum 118 through which the winged shaft 104 protrudes. The fixing drum 122 is generally cylindrical and is attached to a fixing handle 132 that includes a locking part 134 for the latching mechanism 130. The fixing drum 122 is attached to the fixing handle 132 directly or through a mechanical linkage. The fixing drum 122 includes a central slotted hole having substantially the same shape and dimensions as the slotted holes of the tool drum 118 and the trigger drum 120 through which the winged shaft 104 protrudes. The fixing drum 122 further includes a plurality of fixing holes 135 for securing the fixing drum 122 as described in more detail below.

The winged shaft 104 includes a generally cylindrical shaft 136 and a plurality of winglets 138, which are arranged in two symmetrical pairs along the shaft 136. The winglet end of the winged shaft 104 is attached to a locking plate 140 via a locking screw 142. In alternate embodiments, the winglets 138 can be splines or parts thereof, keys, or pins.

A fixing cover 144 is located along the winged shaft 104, between the locking plate 140 and the fixing drum 122. The fixing cover 144 includes a central slotted hole having substantially the same shape and dimensions as the slotted holes of the tool drum 118, the trigger drum 120, and the fixing drum 122 through which the winged shaft 104 protrudes. In addition, the fixing cover 144 includes a plurality of push-pin receiving holes through which corresponding push pins 146 are inserted. The push pins 146 protrude through the locking plate 140, the fixing cover 144, and the fixing holes 135 to secure the fixing drum 122 to the locking plate 140.

The locking plate 140 includes a recessed groove 148 for receiving the winged shaft 104 and a plurality of push-pin receiving holes through which corresponding push pins 146 are inserted. A locking washer 150 is inserted between the head of the locking screw 142 and the locking plate 140.

Turning now to FIG. 1B, the housing 114 is pivotably connected to a hinge 152 via a hinge pin 154, which is inserted through a plurality of hinge pivot holes 156. The housing 114 is attached to the hinge 152 at a housing pivoting portion 157, which is inserted in a hinge slotted area of the hinge 152.

The hinge 152 includes a locking lever 158, which is attached to the hinge 152 via a lever screw 160. The locking lever 158 is inserted in a lever slot 159, which is located at a bottom end of the hinge 152. A lever spring 162 is positioned within the lever slot 159 for maintaining the locking lever 158 in a closed position. The locking lever 158 includes an actuating end 163 and a locking end 165. The actuating end 163 is actuated by urging the locking lever 158 toward the lever spring 162 to unlock the hinge 152 from a closed position to an open position, as described in more detail below in reference to FIGS. 17-19. When the locking lever 158 is pressed, it rotates around the axis of the lever screw 160 such that the locking end 165 causes the hinge 152 to pivot about the axis of the hinge pin 154 (the Z-axis).

A long bearing 164 and a short bearing 166 are used to rotatably attach a knob 168 to the hinge 152. A plurality of set-screws 170 are screwed into the knob 168 for retaining the long bearing 165 and the short bearing 166 relative to the knob 168.

A knob extension or sleeve 172 is attached to the knob 168 using a threaded end of the knob extension 172. The knob extension 172 is a hollow shaft (or sleeve) that is used for accommodating a tool holder 174, which is inserted into the hollow of the knob extension 172. The tool holder 174 is a hollow shaft that accommodates a tool 176, which includes a ball 178 at an insertion end and a scissors device 180 at an operating end. The tool 176 is inserted into the tool holder 174, as shown. According to the shown embodiment, the scissors device 180 is a three-member claw device. The outer surface of the sleeve 172 may be composed of or coated with an insulating material, such as Teflon, to electrically insulate the operator of the instrument 100 from the sleeve 172 when using an electric tool such as a cauterizing tool. For example, the sleeve 172 is wrapped with a Teflon shrink tube.

FIGS. 2-8 show various views of the laparoscopic instrument 100 in an assembled form and depict representative movements of the trigger handle 128. The tool drum 118, the trigger drum 120, and the fixing drum 122 are assembled together with the housing 114. The trigger handle 128 and the fixing handle 132 are shown in a locked position, which is described in more detail below. The housing 114 and the hinge 152 are shown in a closed position, and the ball 178 is received by the ball-receiving hole 127 of the tool drum 118.

As represented by the phantom lines, the trigger handle 128 is rotated relative to the fixing handle 132 in a counter clock-wise direction (from the locked position) to open the scissors device 180 at the operating end of the tool 176. In general, the rotation of the trigger handle 128 causes the rotation of the tool drum 118, which in turn causes the linear movement of the tool 176. The linear movement of the tool 176 causes an opening/closing movement for the scissors device 180. The relationship between the three drums 118, 120, 122 (also referred to as the drum sandwich assembly) is described in more detail below.

In addition, as best seen in FIG. 3, the position of the shaft 136 (represented by the push-button screw 106) can be aligned with the hinge pivot hole 156 or can be different than the position of the hinge pivot hole 156. For example, the center of the shaft 136 can be at the same distance in the Y-axis direction from the X-axis of the tool 176 as the hinge pivot hole 156. Alternatively, the distance between the center of the shaft 136 and the X-axis of the tool 176 can be smaller or greater than the distance between the hinge pivot hole 156 and the X-axis of the tool 176.

An electrical probe 182 is protruding from and is attached to the housing 114. The electrical probe 182 is electrically coupled to the tool 176 (such as a cauterizing tool) to supply electrical current from an external power supply. For example, electrical current is supplied via the electrical probe 182 to an electrocautery tool 176 for cauterizing organ tissue during a surgical procedure. Alternatively, a hole or plug is formed in the housing 114 for receiving an electrode therein.

Referring to FIGS. 9-11, the tool drum 118, the trigger drum 120, and the fixing drum 122 are sandwiched between the tool cover 110 (located at the top, adjacent to the tool drum 118) and the fixing cover 144 (located at the bottom, adjacent to the fixing drum 122). The push button 102 is located at the top of the drum sandwich assembly—near the tool cover 110—and the locking plate 140 is located at the bottom of the drum sandwich assembly—near the fixing cover 144. The shaft 136 protrudes through each of the fixing cover 144, the fixing drum 122, the trigger drum 120, the tool drum 118, and the tool cover 110. The shaft 136 is attached via the locking screw 142 to the locking plate 140 and via the push-button screw 106 to the push button 102. The shaft 136 also protrudes through the spring 108.

The winglets 138 attached to the shaft 136 are adapted to protrude only through corresponding slots of the tool drum 118, the trigger drum 120, the fixing drum 122, and the fixing cover 144. Depending on whether the push button 102 is in a depressed or un-depressed position, the winglets 138 protrude through only some of the tool drum 118, the trigger drum 120, the fixing drum 122, and the fixing cover 144. Depending on the position of the winglets 138, the rotatable movement of the trigger drum 120 is locked with respect to either the tool drum 118 or the fixing drum 122.

The winglets 138 include a pair of top winglets 138 a and a pair of bottom winglets 138 b. As shown in FIGS. 10-11, the push button 102 is in an un-depressed position in which the top winglets 138 a protrude through the tool drum 118 and the trigger drum 120. In the un-depressed position, the rotatable movement of the trigger drum 120 is fixed with respect to the tool drum 118. If the push button 102 is in a depressed position, the top winglets 138 a rotate within the trigger drum 120 (where the bottom winglets 138 b are located in the un-depressed position), and the bottom winglets 138 b rotate within the fixing drum 122. In the depressed position, the rotatable movement of the trigger drum 120 is fixed with respect to the fixing drum 122. The novel arrangement according to the present invention allows the handles 128, 132 to be rotated regardless of the position of the trigger drum 120 relative to the tool drum 118. This aspect advantageously allows the surgeon to manipulate the handles 128, 132 in any drum position. According to the present invention, instead of having to twist or contort the surgeon's body in order to access a hard-to-reach area of a patient's inner cavity, the surgeon simply rotates the drum to achieve a new position and can continue to manipulate the handles 128, 132, which control the tool 176 inside the patient's body. It is advantageous for the handles 128, 132 to be manipulatable even as they are rotated together around the shaft 136.

Referring to FIGS. 12A-12C, alternative embodiments of the winged shaft 136 of FIGS. 1-11 are shown depicting three different winglet combinations. For ease of understanding, FIG. 12B shows the winged shaft 104 of FIGS. 1-11, including the shaft 136 and the two sets of winglets 138. In an alternative embodiment, shown in FIG. 12A, a winged shaft 1204 a includes a shaft 1236 a and a single set of winglets 1238 a. To accommodate the single set of winglets 1238 a, the holes through which the winged shaft 1204 a protrudes (e.g., slotted hole of a trigger drum 1220 a) are modified to include a single slot 1239 a. Each winglet in the set of winglets 1238 a is spaced to lock at most any two drums together when rotated.

In another alternative embodiment, shown in FIG. 12C, a winged shaft 1204 c includes a shaft 1236 c and three sets of winglets 1238 c approximately 120 degrees apart. To accommodate the three sets of winglets 1238 c, the holes through which the winged shaft 1204 c protrudes (e.g., slotted hole of a trigger drum 1220 c) are modified to include three slots 1239 c.

Referring to FIG. 13, a schematic cross-sectional representation illustrates the relationship between a winged shaft 1304 and a plurality of drums, a tool drum 1318, a trigger drum 1320, and a fixing drum 1322, and various positions of the winged shaft 1304 relative to the drums 1318, 1320, 1322. The winged shaft 1304 includes a shaft 1336 and a set of two winglets 1338. From left to right, the drums include the tool drum 1318, the trigger drum 1320, and the fixing drum 1322. The drums 1318, 1320, 1322 are housed within a housing 1314 such that each drum can rotate freely unless fixed in place by the winglets 1338. The drums 1318, 1320, 1322 are fixed from rotational movement when the winglets 1338 protrude through corresponding drum slots. Movement of the winged shaft 1304 interlocks one or more of the drums 1318, 1320, 1322 with respect to each other to achieve a desired rotational combination. For example, as described below, movement of the winged shaft 1304 in any of a plurality of positions A-F achieves any desired rotational combination for the drums 1318, 1320, 1322. As shown in FIG. 13, the winglet and drum combinations can be used to provide a sort of “binary logic” for mechanical devices, such as gears and clutches. The versatility of using the winglets and the drums in accordance with the present invention allows any combination of drum movements to be realized. The concepts of FIG. 13 and related embodiments can be implemented in any mechanical system, including laparoscopic instruments. The present invention expressly contemplates that the lock-and-release embodiments shown and described herein is not limited to laparoscopic instruments.

At position A, the winglets 1338 are positioned to the right of the fixing drum 1322. In this position, each of the drums 1318, 1320, 1322 is free to rotate with respect to each other.

At position B, the winged shaft 1304 is moved toward the drums 1318, 1320, 1322 such that the winglets 1338 are positioned within the fixing drum 1322 only. Accordingly, in this position the fixing drum 1322 is fixed from rotational movement, while the tool drum 1318 and the trigger drum 1320 are free to rotate.

At position C, the winged shaft 1304 is moved further toward the drums 1318, 1320, 1322 such that the winglets 1338 are positioned within both the trigger drum 1320 and the fixing drum 1322. Accordingly, in this position the trigger drum 1320 and the fixing drum 1322 are fixed from rotational movement, while the tool drum 1318 is free to rotate.

At position D, the winged shaft 1304 is moved further toward the drums 1318, 1320, 1322 such that the winglets 1338 are positioned within all three drums. Accordingly, in this position each of the drums 1318, 1320, 1322 is fixed from rotational movement.

At position E, the winged shaft 1304 is moved further toward the drums 1318, 1320, 1322 such that the winglets 1338 are positioned within the tool drum 1318 and the trigger drum 1320. Accordingly, in this position the tool drum 1318 and the trigger drum 1320 are fixed from rotational movement, while the fixing drum 1322 is free to rotate.

At position F, the winged shaft 1304 is moved further toward the drums 1318, 1320, 1322 such that the winglets 1338 are positioned within the tool drum 1318 only. Accordingly, in this position the tool drum 1318 is fixed from rotational movement, while the trigger drum 1320 and the fixing drum 1322 are free to rotate.

Referring to FIGS. 14-16, a cut-away perspective view of the drums 118, 120, 122 is shown revealing the winged shaft 104 in various positions together with the winglets 138. With reference to these figures, the movement of the winged shaft 104 and of the handles 128, 132 will now be described in more detail. In FIG. 14, the push button 102 is shown in a depressed position, and the handles 128, 132 are shown in a first position. Depressing the push button 102 causes the winged shaft 104 to slide in a direction away from the movement of the push button 102 until the top winglets 138 a are located within the trigger drum 120 and the bottom winglets 138 b are located within the fixing drum 122. In this configuration, the trigger drum 120 and the fixing drum 122 are fixed or locked together, which in turn locks the handles 128, 132 together. In addition, the locking plate 140 and the push pins 146 are correspondingly urged away from the fixing drum 122, which is now disengaged from the locking plate 140 and the push pins 146.

Accordingly, in the depressed position the trigger drum 120 and the fixing drum 122 are locked with respect to each other. Further, because the fixing drum 122 is now disengaged from the locking plate 140 and the push pins 146, the combination of the trigger drum 120 and the fixing drum 122 is free to rotate around the Z-axis (the axis of the winged shaft 104).

In FIG. 15, the push button 102 remains in the depressed position. However, the handles 128, 132 have been rotated counter clock-wise from the first position to a second position. Thus, the only two components that change their position from the first position to the second position are the trigger handle 128 and the fixing handle 132. For example, the position of the tool drum 118 remains unchanged. By rotating the handles 128, 132 to a new position, while maintaining the position of the tool drum 118, a surgeon using the laparoscopic instrument 100 may be able to achieve a better grasping position for the handles 128, 132 without changing the position of the tool 176 inside a patient and without contorting or twisting the surgeon's body to maintain a comfortable and firm grasp.

As can be seen in FIGS. 1A and 9, the fixing handle 132 is secured to the locking plate 140 by inserting the push pins 146 through the fixing holes 135. Three pairs of fixing holes 135 are shown, and each fixing hole pair represents a different handle position (up to three different positions in the embodiment shown in FIG. 1A). When the push button 102 is depressed, the push pins 146 disengage the fixing holes 135, allowing the fixing drum 122 to freely rotate. The force exerted by the spring 108 allows the surgeon to rotate the fixing drum 122 (and thereby the fixing handle 132) until the push pins 146 “click” into alignment with a different set of fixing holes 135. Although three pairs of fixing holes 135 are shown allowing the fixing handle 132 to be rotated among one of three different positions, fewer or additional fixing holes are contemplated in other embodiments to allow the fixing handle 132 to be rotated among a corresponding number of positions. For example, if four positions are desired, four pairs of fixing holes 135 are formed in the fixing drum 122 and spaced according to each desired position. Although two push pins 146 are shown in FIG. 1A, in other embodiments, a different number of push pins is used instead.

In FIG. 16, the push button 102 is shown in the un-depressed position to engage the fixing drum 122 to the locking plate 140 and the trigger drum 120 to the tool drum 118. The winglets 138 are now located within the tool drum 118 and the trigger drum 120 to secure the tool drum 118 and the trigger drum 120 to each other. The push pins 146 engage the fixing drum 122, fixing the handles 128, 132 in a second position. When the tool drum 118 and the trigger drum 120 are fixed relative to each other, i.e., in the un-depressed position, the trigger handle 128 may be partially rotated. The rotation of the trigger handle 128 causes the rotation of the tool drum 118, which in turn causes the linear movement of the tool 176. The linear movement of the tool 176 allows the surgeon to use the operating end of the tool 176. For example, a counter clock-wise movement of the trigger handle 128 causes the opening of the scissors device 180, while a clock-wise movement of the trigger handle 128 causes the closing of the scissors device 180.

Referring to FIGS. 17-19, there is shown a shotgun subassembly of the laparoscopic instrument 100 in an open “breech” position. The term “shotgun” subassembly refers to the resemblance of the laparoscopic instrument 100 to the breech of a shotgun, which allows the surgeon to replace the laparoscopic tool without removing the instrument 100 from the patient's body. While the instrument 100 is inserted into the patient's body, the shotgun subassembly can be opened and closed like a shotgun to expose one end of the tool for removal and reinsertion. The laparoscopic instrument 100 includes a hinge portion 1700 and a housing portion 1702, which together form the shotgun subassembly having a “breech” that is pivotable about a hinge 152. The hinge portion 1700 generally includes the hinge 152, the tool 176, and the scissors device 180. The housing portion 1702 generally includes the housing 114, the handles 128, 132, and the drums 118, 120, 122. The pivoting of the hinge 152 with respect to the housing 114 of the laparoscopic instrument 100 is described in more detail in connection with FIGS. 18 and 19. In FIG. 17, the hinge 152 is assembled to the housing pivoting portion 157 using the hinge pin 154. The housing 114 pivots about the hinge pin 154 in the Z-axis to provide the opening and/or closing movement of the housing portion 1702 with respect to the hinge portion 1700.

In FIGS. 18 and 19, the hinge portion 1700 is shown in an open position, having been pivoted in a counter clock-wise direction about the Z-axis from the closed position. As the hinge portion 1700 is urged toward the open position, the ball 178—along with the tool 176—is retracted from the ball-receiving hole 127 of the tool drum 118. To open the hinge portion 1700, the locking lever 158 is pressed in a direction toward the tool 176 (as described earlier in reference to FIG. 1B) such that the locking end 165 (shown in FIG. 1B) releases the housing pivoting portion 157. As the hinge portion 1700 is urged toward the open position, the ball 178 passes through the ball-receiving slot 115 formed in the housing 114 until the ball 178 exits the ball-receiving slot 115. After moving the hinge portion 1700 into the open position, the surgeon can remove the tool 176 from within the hinge portion 1700 and replace it with another laparoscopic tool without removing any other part of the instrument 100 from the patient's body. Thus, during the tool replacement, the knob extension or sleeve 172 remains inside the patient in a fixed position. In other words, in contrast to prior art laparoscopic instruments, the surgeon is not required to remove the instrument 100 from within the patient in order to replace the tool 176 with another tool. Maintaining the instrument 100 inside the patient while exchanging tools advantageously eliminates the need for the surgeon to search for and find a previously located body part or position.

The location of the ball-receiving hole 127 is found by drawing a circle about the hinge pin 154, whose radius extends to the end of the ball 178 (when the tool 176 is fully inserted into the knob extension 172). Where the circle intersects the tool drum 118 is where the manufacturer should form the ball-receiving hole 127.

In an alternate embodiment, instead of adapting the hinge portion 1700 to swing open, the hinge portion 1700 is adapted to slide open. For example, instead of having the housing 114 rotatable with respect to the hinge 152, the housing 114 slides open with respect to the hinge 152 in, for example, a direction of the Z-axis, to allow the removal and/or insertion of the tool 176.

Referring to FIGS. 20A and 20B, an alternative embodiment of the present invention shows a laparoscopic instrument 2000 that includes a housing 2014 and a hinge 2052. The hinge 2052 pivots around an X-axis of the laparoscopic instrument 2000. Specifically, the hinge 2052 pivots around a hinge pin 2052, which is inserted through a hinge pivot hole 2056, with respect to the housing 2014.

Referring to FIGS. 21A and 21B, an alternative embodiment of the present invention shows a laparoscopic instrument 2100 that includes a housing 2114 and a hinge 2152. The hinge 2152 pivots around a Y-axis of the laparoscopic instrument 2100. Specifically, the hinge 2152 pivots around a hinge pin 2152 with respect to the housing 2114. Slots in the housing 2014 and 2114, respectively, and respective drums will enable the exposed part of each respective shaft and ball to travel into each respective drum.

Referring to FIGS. 22A-23B, the locking of the trigger handle 128 with respect to the fixing handle 132 will be described in more detail. In FIG. 22A, the handles 128, 132 are in an open and aligned position relative to one another. In the open position there is no contact between the latching mechanism 130 of the trigger handle 128 and the locking part 134 of the fixing handle 132. The latching mechanism 130 and the locking part 134 include a plurality of corresponding teeth 2282 that are biased so as to lock the handles 128, 132 to each other, as described in more detail below in reference to FIG. 22B.

The trigger handle 128 further includes a latching lever 2284, which is pivotally connected to the trigger handle 128 at a pivoting point 2286, and a lever limiter 2288. The lever limiter 2288 limits the rotational movement of the latching lever 2284 to a distance that is sufficient for disengaging engaged ones of the teeth 2282. A reason for limiting the rotational movement of the latching lever 2284 is to prevent the latching lever 2284 from interfering with the operation of the laparoscopic instrument 100. The latching mechanism 130 is mounted on the latching lever 2284 such that the latching mechanism 130 moves whenever the latching lever 2284 is moved. The aligned position shows the latching lever 2284 parallel to the fixing handle 132 in the X-Y plane.

In FIG. 22B, the handles 128, 132 are shown in a locked position, and the handles 128, 132 are correspondingly in a closed and aligned position. The latching mechanism 130 and the locking part 134 are interlocked via the plurality of corresponding teeth 2282, which are included in each of the latching mechanism 130 and the locking part 134. To lock the handles 128, 132, at least one of the handles 128, 132 is rotated around the Z-axis toward the other one of the handles 128, 132. For example, the trigger handle 128 is rotated in a clockwise direction toward the fixing handle 132. Corresponding ones of the teeth 2282 are engaged via frictional forces to prevent movement of the handles 128, 132 toward an open position. The teeth 2282 are biased to encourage movement of the handles 128, 132 toward one another but to resist movement of the handles 128, 132 away from one another. The ability to lock the handles 128, 132 during surgery advantageously frees the surgeon's hand to carry out other tasks, while leaving the instrument 100 inside the patient's body. It further permits the surgeon to relax the hand gripping the instrument 100 to minimize hand fatigue that can be caused by prolonged grasping and manipulation of the handles 128, 132. Still further, without locking handles, if the surgeon's hand that is grasping the handles 128, 132 were to momentarily relax or lose its grip, the tool 176 may slip or dislodge from a desired position inside the patient's body cavity. When the handles 128, 132 are in the locked position, the tool 176 can be reliably maintained inside the patient. With the handles locked, the surgeon may also rotate them together in accordance with the present invention to a better position without disturbing the position of the tool 176 inside the body cavity.

In FIG. 23A, the handles 128, 132 are shown in a closed and offset position. The handles 128, 132 are fixed with respect to the Z-axis as the latching lever 2284 is urged in the Z-axis direction to unlock the latching mechanism 130 from the locking part 134. When the latching mechanism 130 is moved in the Z-axis direction away from the locking part 134, via movement of the latching lever 2284, engaged ones of the teeth 2282 disengage, causing the trigger handle 128 to unlock from the fixing handle 132.

In FIG. 23B, the handles 128, 132 are shown in an open and offset position. After the trigger handle 128 is moved in the Z-axis direction (as shown in FIG. 23A) away from the fixing handle 132, the trigger handle 128 is rotated in a counter-clockwise direction around the Z-axis. To position the latching lever 2284 in the initial open and aligned position of FIG. 22A, the latching lever 2284 must be urged in the Z-axis direction toward the trigger handle 128 in order to position the latching lever 2284 in the same X-Y plane as the fixing handle 132. Now, the trigger handle 128 is ready to be locked relative to the fixing handle 132.

Preferably, the latching lever 2284 is positioned to be manipulatable by the surgeon with a single finger, such as with the pinky finger of the hand grasping the handles 128, 132. In this respect, the surgeon is not required to remove the hand from the handles 128, 132 in order to lock or unlock them. In operation, the surgeon simply moves the latching lever 2284 with the pinky finger, which is typically not positioned within the handle 128 as are the ring and middle fingers.

At least some of the parts described above in reference to FIGS. 1A-23B are injection-molded parts, which are precision molded with hot-oil or water molds using high-strength, graphite-, glass-, or carbon-filled plastics such as PEEK™ (polyetheretherketone), Ultem® (polyetherimide), Grivory®, or RADEL® R (polyphenylsulfone). The injection-molded parts include single cavity molds and family molds. For example, some of the molded parts can be cold runner molds.

Although the foregoing embodiments have been described in connection with a laparoscopic instrument 100, the present invention is equally applicable to an arthroscopic instrument.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and herein described in detail. It should be understood, however, that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. 

1. A laparoscopic instrument, comprising: a first handle including a latching mechanism; and a second handle pivotally coupled to the first handle and including a locking part, the first handle and the second handle being in a locked position when the latching mechanism is engaged with the locking part, the first handle and the second handle being in an open position when the latching mechanism is disengaged from the locking part.
 2. The laparoscopic instrument of claim 1, wherein the latching mechanism includes at least one latching tooth and the locking part includes at least one locking tooth, the latching tooth being engaged to the locking tooth in the locked position.
 3. The laparoscopic instrument of claim 1, wherein the latching mechanism further includes a latching lever pivotably coupled to the first handle.
 4. The laparoscopic instrument of claim 3, wherein the latching lever is aligned with the first handle in the locked position.
 5. The laparoscopic instrument of claim 3, wherein a free end of the latching lever is pivotable in a direction away from the first handle to achieve the open position.
 6. The laparoscopic instrument of claim 3, wherein the latching mechanism further includes a lever limiter positioned along the rotational path of the latching lever for limiting the rotation of the latching lever.
 7. The laparoscopic instrument of claim 6, wherein the lever limiter is coupled proximate a free end of the latching lever.
 8. The laparoscopic instrument of claim 1, wherein the latching mechanism includes a latching teeth-engaging part attached to a free end of a latching lever, the locking part including a locking teeth-engaging part, the latching lever being pivotally coupled to the first handle at a fixed end, the latching lever being aligned with the first handle in the locked position, the latching teeth-engaging part being aligned and engaged to the locking teeth-engaging part when the first handle is in the locked position.
 9. A method of locking and unlocking a first handle of a laparoscopic instrument relative to a second handle, comprising: urging the first handle towards the second handle to engage a latching mechanism of the first handle to a locking part of the second handle.
 10. The method of claim 9, further comprising biasing the latching mechanism against the locking part to secure a plurality of teeth to each other.
 11. The method of claim 10, wherein at least one of the plurality of teeth is located on the latching mechanism and a corresponding one of the plurality of teeth is located on the locking part.
 12. The method of claim 9, further comprising pivoting the latching mechanism away from the first handle to unlock the first handle from the second handle.
 13. The method of claim 9, further comprising: mounting the latching mechanism on a latching lever pivotally coupled to the first handle; and rotating a free end of the latching lever to disengage the latching mechanism from the locking part.
 14. The method of claim 13, further comprising limiting the pivoting motion of the latching lever using a lever limiter.
 15. The method of claim 14, wherein the lever limited is coupled to the first handle proximate the free end of the latching lever.
 16. The method of claim 13, further comprising rotating the free end of the latching lever in a direction that is substantially perpendicular to the pivoting direction of the first handle towards the second handle.
 17. The method of claim 9, further comprising coupling the latching mechanism to a grasping end of the first handle.
 18. The method of claim 9, further comprising coupling the locking part to a grasping end of the second handle.
 19. A laparoscopic instrument having a pair of handles that are pivotable between a locked position and an open position, comprising: a latching lever pivotally coupled to a trigger handle of the pair of handles at a pivoting point; a lever limiter coupled to the trigger handle proximate a free end of the latching lever, the lever limiter restricting pivoting motion of the latching lever; a tooth-engaging part coupled to the trigger handle; and a locking part coupled to a fixing handle of the pair of handles such that the locking part is engaged to the tooth-engaging part when the pair of handles is in the locked position, and such that the locking part is disengaged from the tooth-engaging part when the pair of handles is in the open position.
 20. The laparoscopic instrument of claim 19, wherein the locking part is biased towards the tooth-engaging part via a frictional force exerted by at least one pair of interlocking teeth. 